1. Field of the Invention
The present invention relates generally to a home network solution, and in particular, to a backbone home network configuration based on the IEEE (Institute of Electrical and Electronics Engineers) 1394 standard.
2. Description of the Related Art
Existing transmission techniques proposed to be used in a home network include: Ethernet, cable wires, home PNA (Phoneline Networking Alliance), IEEE 1394, and WLL (Wireless Local Loop). Sufficient bandwidth and QoS (Quality of Service) guarantee are important factors in the multimedia transmission. To this end, the IEEE 1394 is well known as the best scheme that can satisfy these requirements and highly likely to be adopted as the standard for the current home network solutions.
FIG. 1 illustrates a typical IEEE 1394 daisy-chain configuration. As shown, the IEEE 1394 is a transmission standard based on a tree topology in which all devices are connected to one another in a daisy-chain fashion. In particular, the IEEE 1394 daisy chain is configured to include a gateway 100 for connection to a higher network, sockets 101-1, 101-2 and 101-3 for connection to the lower cluster networks, and the cluster networks. Each cluster network comprises a branch node(s) 102-1, 102-2, 102-3 or 102-4 and a leaf node 103-1, 103-2 or 103-3.
The IEEE 1394 is designed in such a manner so that real-time isochronous transmission and asynchronous transmission can be carried out simultaneously with automatic setting, plug & play, and hot plug functions. Hence, it is an ideal to the household application that demands various types of data and convenience.
FIG. 2 illustrates an exemplary bus reset that occurs when a device is removed in the IEEE 1394 daisy-chain configuration between a PC (Personal Computer) and its peripheral devices. As shown in FIG. 2, the IEEE 1394 undergoes reset and reconfiguration of all nodes connected to a bus unit whenever an event occurs, such as power-on/off or addition/removal of a device (serving as a node) connected to the unit bus. As a result, frequent addition and removal of a product, such as a digital camcorder, in the household significantly impairs the overall stability of a system.
For example, if a device 2 moves from position 22 to position 23 in a daisy-chain structure with device 1 (21), device 2 (22) and device 3(24), all nodes connected to each bus, namely device 1 and device 3 needs to be reset and reconfigured. At the same time, data is abruptly disconnected from lower-layer device 3, thus incurring data loss.
To activate a device acting as a leaf node, its branch node must be turned on. As the devices are connected to a service gateway (SG) serving as a central station by transmission lines in a one-to-one correspondence in the conventional tree topology, the cable installation cost increases with the size of an indoor area. In addition, the number of optical transceivers is increased which dominates the cost of the whole system in a 400 or higher-Mbps indoor network, thereby imposing cost constraints.